Derrick-sheave or crown-pulley.



PATENTED JUNE 20, 1905.

J. B. FORKER.

DERRICK SHE AVE OR CROWN PULLEY.

APPLICATION FILED NOV.14, 1904.

Patented June 20, 1905.

PATENT FFICE.

JAMES B. FORKER, OF OIL CITY, PENNSYLVANIA, ASSIGNOR TO OIL WELL SUPPLYCOMPANY, OF PITTSBURG, PENNSYLVANIA, A COR- PORATION OF PENNSYLVANIA.

DERRICK-SHEAVE OR CROWN-PULLEY.

SPECIFICATION forming part of Letters Patent No. 792,768, dated June 20,1905.

Application filed November 14, 1904. Serial No. 232,768.

To all whom, it may concern/,-

Be it known thatI, J AMES B. FoRKnR, a citizen of the United States,residing at Oil City, in the county of Venango and State ofPennsylvania, have invented new and useful Improvements in Derrick-Sheaves or Crown- Pulleys, of which the following is a specification,reference being bad to the accompanying drawings, forming part of thesame,in which Figure 1 is a side elevation of a portion of a derrick,showing a crown-pulley or derricksheave embodying the invention,together with portions of a composite drilling-cable with which saidsheave or pulley is designed to be used. Fig. 2 is a detached enlargedside elevation of the derrick-sheave or crownpulley. Fig. 3 is atransverse section of the sheave or pulley on the line 3 3, Fig. 2, therelation of the drill-cable to the pulley when traversing the same beingindicated by dotted lines. Fig. 4 is a view of the adjacent ends of thewire and manila sections forming the composite cable and one meanswhereby the sections may be connected.

Like symbols refer to like parts wherever they occur.

Heretofore in drilling deep wells, such as oil or Artesian wells, thecommon practice has been to employ manila cables, because the spring oryield of the rope produced a whip stroke or quick lift of the tool,which greatly added to the efficiency thereof; but such ca bles havebeen found objectionable as liable to deteriorate from wear throughcontact with the rough walls of the well and as not economic of power byreason of the manila cable becoming water-soaked and when ofconsiderable length thus adding to the weight to be lifted at eachstroke of the tools. To overcome these objections, attempts have beenmade to employ wire cables in drilling deep wells; but these lacked theefficiency of the manila cable, as they were found to be deficient inspring or reaction, which affected the quilck lift and added to theefficiency of the dri 1.

To avoid objectionable features of both manila and wire drill-cables andto obtain the advantages of both, composite drill-cables, made up ofsections of wire, and manila cables have been tried, the main length ofthe cable being of wire and the shorter section adjacent to thedrill-tool being of manila, and this while found effective has been alsofound liable to deterioration by reason of the distortion and wear ofthe drilling-cable as it traverses the pulley or sheave, and, further,the sheave or pulley has been subject to deterioration by reason of thetwist or binding of its journals where the cable has been permitted toslip or have a movement on the face of the pulley. To overcome theseseveral objections and produce a derricksheave or crown-pulley whichshall be efficient and durable and which shall not cause thedeterioration of the drilling-cable when employed in conjunction with acomposite cable is the object of the present invention, and to effectthe same a pulley or sheave is provided on its periphery with aplurality of uninterrupted concentric grooves, one within the other,said grooves having different diameters corresponding with the diametersof the different sections of the cable, said grooves being substantiallysemicircular as to the cable-receiving sections and having their centersin the same plane, whereby the spreading and distortion of thedrilling-cable are prevented as it traverses the pulley and any sideslip of the cable which would tend to cause binding and unequal wear ofthe bearings of the pulley is overcome, and such a construction embodiesthe main feature of this invention.

In some instances the means for connecting the wire and manila sectionsof the composite cable will exceed in diameter the manila or largersection, and in order that the same may I will now proceed to describethe invention more fully, so that others skilled in the art to which itappertains may apply the same.

In the drawings, A indicates the top section or crown of a derrick, andB the derricksheave or crown-pulley journaled therein and over whichpasses the drill-cable, which in the present instance is indicated by Cand is composed of sections 0 0 of different diameter, the former, 0,which constitutes the upper or main portion of the drilling-cable, beingof wire, while the latter, 0, or tool-section, is of manila, the twosections being united in any suitable manner-as, for instance, by thethimble d, links 0, and clamp f, as indicated in Fig. 4 of the drawings.

The crown-pulley B may be of the usual or any required diameter andwidth of periphery and is provided with suitable journals 6, by means ofwhich it is journaled in hearings on the crown of the derrick A. Theperiphery of the pulley is provided with a main groove 1 of curvedcross-section, the diameter of which is such as to accommodate withoutlost movement a manila cable of the required diameter, and in the bottomof said groove 1 and centrally thereof is provided an inner groove 2,also of curved cross-section and of approximately one-fourth thediameter of the outer groove 1 or of such diameter as will accommodatethe wire cable of desired size without cramping or binding, yet withoutlost motion. The groove 2 is of a depth substantially equal to theradius of its circle, and the grooves 1 and 2 are concentricallydisposed. and in the same plane as to their centers. Exterior to themain groove 1 the periphery of the sheave or pulley is formed withcurved flaring lips 3 3, which in effect constitute when taken togethera supplementary or outer groove on the arc of a circle of greaterdiameter than main groove 1, adapted to accommodate the connectionswhich unite the sections of the composite cable at the instant they aretraversing the sheave or pulley. While the main and inner grooves 1 and2 are of different diameters, as before noted, yet each is of uniformdiameter throughout its length.

When the pulley is in service, the inner groove 2 will accommodate thewire section of the composite cable and will prevent the flattening ordistortion thereof under the weight of the drill-tools and at the sametime prevent any lateral or transverse movement of the weighted cable,which would tend to bind the pulley and cause unequal wear of itsjournals, and when the drill-tools are drawn up the main groove 1 willaccommodate and support the manila section of the cable, and in bothinstances the cable and its lead are carried centrally of the sheave orpulley and binding or cramping of the pulley-bearings avoided.

As the depth of the inner groove 2 is equal to substantially half thediameter of the Wire cable it is intended to carry, it is evidentthatthe edges formed at the junction of grooves 1 and 2 will not be sopresented to the manila cable, which is of greater diameter, as to fraythe same when the manila cable is traversing the pulley.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is

1. A derrick-sheave or crown-pulley for composite drilling-cables, saidsheave or pulley having a plurality of concentrically disposeduninterrupted grooves of different widths and curved cross-section.

2. A derrick-sheave or crown-pulley, said sheave or pulley having aplurality of concentrically-disposed uninterrupted grooves ofdifferentwidths and curved cross-section, the groove of lesser width having adepth substantially equal to the radius of its circle.

3. A derrick-sheave or crown-pulley, said sheave or pulley having aplurality of concentrically-disposed uninterrupted grooves of differentwidths and curved cross-section, the depths of each of said groovesbeing substantially equal to the radius of its circle.

4:. A derrick-sheave or crown-pulley for composite drilling-cables, saidsheave or pulley having two uninterrupted grooves of differentdiameters, one groove being located within the other, each groove beingof uniform diameter throughout its extent, said sheave or pulley beingprovided with curved flaring peripheral lips exterior to the main grooveof said pulley, substantially as and for the purposes specified.

In testimony whereof I affix my signature in presence of two subscribingwitnesses.

JAMES B. FORKER.

Vitnesses:

J UDsoN D. TRAX, MABEL BOYER.

